Down Came the Rain by Burgess Clark

Eighteen-year-old Michael and his fourteen-year-old brother Brucie -- who has been considered mentally "slow" since birth -- venture out on a camping trip together. Brucie's never-ending curiosity becomes increasingly unbearable to Michael, especially when the questions involve the death of their mother. Down Came the Rain is a touching, sad, and ultimately hopeful exploration of two vastly different brothers, and how they navigate the delicacy of family and truth.